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1.
Org Lett ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38917369

RESUMO

Spirocyclic compounds are abundant in biologically active products. However, the divergent synthesis of spirocyclic compounds using low-cost and abundant available starting materials remains a challenge. Herein, we report an effective method for producing spirocyclic motifs using a cyclic ß-carbonyl ester or amide and ethylene via thianthrenation. This strategy highlights the exciting possibility of utilizing abundant ethylene as a C-2 synthon and allows regulating the core structure of the spirocyclic compound by simply altering the base type.

2.
Angew Chem Int Ed Engl ; : e202408321, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926096

RESUMO

exo-6b2-Methyl-substituted pentabenzocorannulene (exoPBC-Me) was synthesized by the palladium-catalyzed cyclization of 1,2,3-triaryl-1H-cyclopenta[l]phenanthrene. Its bowl-shaped geometry with an sp3 carbon atom in the backbone and a methyl group located at the convex (exo) face was verified by X-ray crystallography. According to DFT calculations, the observed conformer is energetically more favorable than the endo one by 39.9 kcal/mol. Compared to the nitrogen-doped analogs with intact π-conjugated backbones (see the main text), exo-PBC-Me displayed a deeper bowl depth (avg. 1.93 Å), redshifted and broader absorption (250-620 nm) and emission (from 585 to more than 850 nm) bands and a smaller optical HOMO-LUMO gap (2.01 eV). exo-PBC-Me formed polar crystals where all bowl-in-bowl stacking with close π···π contacts is arranged unidirectionally, providing the potential for applications as organic semiconductors and pyroelectric materials. This unusual structural feature, molecular packing, and properties are most likely associated with the assistance of the methyl group and the sp3 carbon atom in the backbone.

3.
Nat Commun ; 15(1): 4744, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38834549

RESUMO

Developing mild photocatalytic bromination strategies using sustainable bromo source has been attracting intense interests, but there is still much room for improvement. Full utilization of redox centers of photocatalysts for efficient generation of Br+ species is the key. Herein we report heterogenous organophotocatalytic HBr oxidation coupled with oxygen reduction to furnish Br2 and H2O2 for effective bromination of arenes over Al2O3 supported perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA). Mechanism studies suggest that O-vacancy in Al2O3 can provide Lewis-acid-type anchoring sites for O2, enabling unexpected dual-electron transfer from anchored photoexcited PTCDA to chemically bound O2 to produce H2O2. The in-situ generated H2O2 and Br2 over redox centers work together to generate HBrO for bromination of arenes. This work provides new insights that heterogenization of organophotocatalysts can not only help to improve their stability and recyclability, but also endow them with the ability to trigger unusual reaction mode via cooperative catalysis with supports.

4.
Cell Metab ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38906140

RESUMO

Low-density lipoprotein receptor-related protein-1 (LRP1) is an endocytic/signaling cell-surface receptor that regulates diverse cellular functions, including cell survival, differentiation, and proliferation. LRP1 has been previously implicated in the pathogenesis of neurodegenerative disorders, but there are inconsistencies in its functions. Therefore, whether and how LRP1 maintains brain homeostasis remains to be clarified. Here, we report that astrocytic LRP1 promotes astrocyte-to-neuron mitochondria transfer by reducing lactate production and ADP-ribosylation factor 1 (ARF1) lactylation. In astrocytes, LRP1 suppressed glucose uptake, glycolysis, and lactate production, leading to reduced lactylation of ARF1. Suppression of astrocytic LRP1 reduced mitochondria transfer into damaged neurons and worsened ischemia-reperfusion injury in a mouse model of ischemic stroke. Furthermore, we examined lactate levels in human patients with stroke. Cerebrospinal fluid (CSF) lactate was elevated in stroke patients and inversely correlated with astrocytic mitochondria. These findings reveal a protective role of LRP1 in brain ischemic stroke by enabling mitochondria-mediated astrocyte-neuron crosstalk.

5.
Org Lett ; 26(19): 4098-4103, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38708839

RESUMO

C-1-deuterated aldehydes are essential building blocks in the synthesis of deuterated chemicals and pharmaceuticals. This has led chemists to devise mild methodologies for their efficient production. Ideally, hydrogen-deuterium exchange (HDE) is the most effective approach. However, the traditional HDE for creating C-1-deuterated aldehydes often requires a complex system involving multiple catalysts and/or ligands. In this study, we present a mild photocatalytic HDE of the formyl C-H bond with D2O. This process is facilitated by chlorine radicals that are generated in situ from low-cost FeCl3. This strategy demonstrated a broad reaction scope and high functional group tolerance, affording good yields and ≤99% D incorporation. To bridge the gap between research and industrial applications, we designed a new flow photoreactor equipped with a high-intensity light-emitting diode bucket, enabling the synthesis of C-1-deuterated aldehydes on a scale of 85 g. Finally, we successfully produced several important deuterated aldehydes that are integral to the synthesis of deuterated pharmaceuticals.

6.
Eur J Med Res ; 29(1): 286, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38745338

RESUMO

BACKGROUND: Our study aimed to confirm a simplified radiological scoring system, derived from a modified Reiff score, to evaluate its relationship with clinical symptoms and predictive outcomes in Taiwanese patients with noncystic fibrosis bronchiectasis (NCFB). METHODS: This extensive multicenter retrospective study, performed in Taiwan, concentrated on patients diagnosed with NCFB verified through high-resolution computed tomography (HRCT) scans. We not only compared the clinical features of various types of bronchiectasis (cylindrical, varicose, and cystic). Furthermore, we established relationships between the severity of clinical factors, including symptom scores, pulmonary function, pseudomonas aeruginosa colonization, exacerbation and admission rates, and HRCT parameters using modified Reiff scores. RESULTS: Data from 2,753 patients were classified based on HRCT patterns (cylindrical, varicose, and cystic) and severity, assessed by modified Reiff scores (mild, moderate, and severe). With increasing HRCT severity, a significant correlation was found with decreased forced expiratory volume in the first second (FEV1) (p < 0.001), heightened clinical symptoms (p < 0.001), elevated pathogen colonization (pseudomonas aeruginosa) (p < 0.001), and an increased annual hospitalization rate (p < 0.001). In the following multivariate analysis, elderly age, pseudomonas aeruginosa pneumonia, and hospitalizations per year emerged as the only independent predictors of mortality. CONCLUSION: Based on our large cohort study, the simplified CT scoring system (Reiff score) can serve as a useful adjunct to clinical factors in predicting disease severity and prognosis among Taiwanese patients with NCFB.


Assuntos
Bronquiectasia , Índice de Gravidade de Doença , Humanos , Masculino , Feminino , Bronquiectasia/fisiopatologia , Bronquiectasia/diagnóstico por imagem , Taiwan/epidemiologia , Pessoa de Meia-Idade , Prognóstico , Idoso , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Volume Expiratório Forçado , Adulto , Pseudomonas aeruginosa/isolamento & purificação
7.
Network ; : 1-53, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578214

RESUMO

This work chiefly explores fractional-order octonion-valued neural networks involving delays. We decompose the considered fractional-order delayed octonion-valued neural networks into equivalent real-valued systems via Cayley-Dickson construction. By virtue of Lipschitz condition, we prove that the solution of the considered fractional-order delayed octonion-valued neural networks exists and is unique. By constructing a fairish function, we confirm that the solution of the involved fractional-order delayed octonion-valued neural networks is bounded. Applying the stability theory and basic bifurcation knowledge of fractional order differential equations, we set up a sufficient condition remaining the stability behaviour and the appearance of Hopf bifurcation for the addressed fractional-order delayed octonion-valued neural networks. To illustrate the justifiability of the derived theoretical results clearly, we give the related simulation results to support these facts. Simultaneously, the bifurcation plots are also displayed. The established theoretical results in this work have important guiding significance in devising and improving neural networks.

8.
J Org Chem ; 89(6): 4120-4127, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38439707

RESUMO

Heteroatom-adjacent C(sp3) radical cyclization of N-arylacrylamides provides a straightforward pathway to synthesize valuable 3-functionalized oxindoles. Traditional cyclization reactions normally require harsh conditions or transition-metal catalysts. Here, we developed a metal-free, diversity-oriented synthesis of 3-functionalized oxindoles via photochemically induced selective cleavage of C(sp3)-H bonds. A variety of 3-substituted oxindoles with functionalities such as ethers, polyhalogens, benzyl, and formyl groups can be obtained by a rational design. This strategy is characterized by its simple operation and mild conditions, aligning well with the developmental requirements for sustainable chemistry. The gram-scale continuous-flow synthesis and efficient construction of bioactive molecules highlight its practical utility.

9.
Animal Model Exp Med ; 7(1): 71-76, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38375555

RESUMO

The rodent running-wheel recording apparatus is a reliable approach for studying circadian rhythm. This study demonstrated how to construct a simple and intelligent running-wheel recording system. The running wheel was attached to the cage's base, whereas the Hall sensor was attached to the cage's cover. Then, the RJ25 adaptor relayed the running signal to the main control board. Finally, the main control board was connected to the USB port of the computer with the USB connection. Data were collected using the online-accessible, self-created software Magturning. Through Magturning, generated data were saved and exported in real time. Afterward, the device was validated by collecting data on the locomotor activities of mice under different light conditions. In conclusion, this new device can record circadian activity of rodents. Our device is appropriate for interdisciplinary investigations related to biological clock research.


Assuntos
Relógios Biológicos , Ritmo Circadiano , Camundongos , Animais
10.
Heliyon ; 10(4): e25749, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38390194

RESUMO

Background: Acute respiratory distress syndrome (ARDS) is associated with high mortality. The impacts of body mass index (BMI) on the morality of older patients with ARDS remain unclear. Methods: This is a single-center cohort study which was conducted at Taichung Veterans General Hospital, Taiwan. Adult patients admitted to the ICU needing mechanical ventilation with ARDS were included for analysis. We compared the data of older patients (age ≥65 years) with those of younger patients (Age <65 years). The factors associated with in-hospital mortality of older patients were investigated. Results: This study included a total of 728 (mean age: 66 years; men: 63%) patients, and 425 (58.4%) of them aged ≥65 years. Older patients exhibited lower body mass index (BMI) (23.8 vs 25.2), higher Acute Physiology and Chronic Health Evaluation (APACHE) II scores (28.9 vs 26.3), higher Charlson Comorbidity Index (CCI) (4.0 vs 3.4), and lower Sequential Organ Failure Assessment (SOFA) scores (10.0 vs 11.1) than younger patients. Furthermore, older patients had mortality rates similar to younger patients (40.5% vs 42.9%, P = 0.542), but had longer length of stay in the ICU (17.6 vs 15.6 days, P = 0.047). For older patients, BMI <18.5 (odds ratio [OR], 2.78; 95% confidence interval [CI], 1.45-5.34), high SOFA score (OR, 1.20; 95% CI, 1.12-1.28), and moderate (OR, 1.95; 95% CI 1.20-3.14) or severe ARDS (OR, 2.30; 95% CI 1.26-4.22) were independent risk factors for mortality. Conclusions: In this cohort, critical ill older patients with ARDS had lower BMI, more comorbidities, and higher APACHE II scores than younger patients. Mortality rate was similar between older and younger patients. Low BMI, high SOFA score, and moderate or severe ARDS were independently associated with mortality in older patients with ARDS.

11.
PLoS One ; 18(12): e0295261, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38091325

RESUMO

BACKGROUND: Acute respiratory distress syndrome (ARDS) is a common life-threatening condition in critically ill patients. Itis also an important public health issue because it can cause substantial mortality and health care burden worldwide. The objective of this study was to investigate therisk factors that impact ARDS mortality in a medical center in Taiwan. METHODS: This was a single center, observational study thatretrospectively analyzed data from adults in 6 intensive care units (ICUs) at Taichung Veterans General Hospital in Taiwan from 1st October, 2018to30th September, 2019. Patients needing invasive mechanical ventilation and meeting the Berlin definition criteria were included for analysis. RESULTS: A total of 1,778 subjects were screened in 6 adult ICUs and 370 patients fulfilled the criteria of ARDS in the first 24 hours of the ICU admission. Among these patients, the prevalenceof ARDS was 20.8% and the overall hospital mortality rate was 42.2%. The mortality rates of mild, moderate and severe ARDS were 35.9%, 43.9% and 46.5%, respectively. In a multivariate logistic regression model, combination of driving pressure (DP) > 14cmH2O and oxygenation (P/F ratio)≤150 was an independent predictor of mortality (OR2.497, 95% CI 1.201-5.191, p = 0.014). Patients with worse oxygenation and a higher driving pressure had the highest hospital mortality rate(p<0.0001). CONCLUSIONS: ARDS is common in ICUs and the mortality rate remains high. Combining oxygenation and respiratory mechanics may better predict the outcomes of these ARDS patients.


Assuntos
Pulmão , Síndrome do Desconforto Respiratório , Adulto , Humanos , Respiração Artificial/efeitos adversos , Unidades de Terapia Intensiva , Fatores de Risco
13.
Org Lett ; 25(46): 8350-8355, 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-37943664

RESUMO

Herein, we describe a metal-free approach for the cross-coupling of arenes or styryl-thianthrenium salts (TTs) with diarylphosphines via an electron donor-acceptor (EDA) complex. Various tertiary phosphines were obtained with high site selectivity and good functional group tolerance. This method enables straightforward construction of C-P bonds via C-H activation of arenes and allows the late-stage functionalization of natural products or pharmaceutical molecules. Mechanistic studies support the approach involving a photoinduced EDA complex.

14.
Cancer Manag Res ; 15: 1251-1262, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37953889

RESUMO

Background: Antiangiogenetic therapy and lung cancer, per se, are associated with an increased risk of thromboembolic events (TE). We aim to evaluate the pattern and outcome of TE as well as its influence on survival time of advanced non-small cell lung cancer (NSCLC) patients receiving antiangiogenic therapy. Methods: This was a retrospective cohort study, which included advanced NSCLC patients receiving antiangiogenic therapy. All TE were confirmed by objective image studies. We disclosed the presentation and risk factors of TE and evaluated its influence on outcome. Results: A total of 427 patients were included. TE occurred in 43 patients (10.1%). Deep vein thrombosis (DVT) was the most common TE (n = 20). Up to 46.2% of DVT did not occur in the typical lower extremities. Two patients died of TE. Among patients with continuous use or reuse of antiangiogenetic therapy, 18.2% had recurrent TE events. At the occurrence of TE, 28 patients experienced progressive disease (TE with PD), while tumor status remained stable in another 15 patients (TE without PD). The post-TE survival of patients without and with PD were 8.9 months (95% CI 3.9-13.9) vs 2.2 months (95% CI 0.1-4.3), P = 0.012. As compared with patients without TE (31.4 months [95% CI 27.1-35.7]), TE with PD patients experienced a significantly shorter overall survival (20.1 months [95% CI 15.5-24.6]), but TE without PD patients had comparable survival time (32.7 months [95% CI 7.4-28.1]) (P = 0006). The use of hormone analogue and proteinuria predicted the events among TE with PD group (aOR 2.79 [95% CI 1.13=6.92]; P = 0.027) and TE without PD group (aOR 4.30 [95% CI 1.13-16.42]; P = 0.033), respectively. Conclusion: Owing to the different risk factors and influences on the survival time, TE with and without PD may be two different disease entities.

15.
Cell Immunol ; 393-394: 104773, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37857190

RESUMO

Immunotherapy for prostate cancer (PCa) faces serious challenges. Therefore, the co-inhibitory receptors that regulate T cell function of PCa must be elucidated. Here we identified that the inhibitory receptor LAG3 was significantly induced in T cells from PCa patients. Gene array analysis revealed that insufficient ataxia telangiectasia mutated (ATM) gene expression in PCa T cells was responsible for the elevated LAG3 expression. Mechanistically, insufficient ATM expression impaired its ability to activate AMPKα signaling and CD4+ T cell functions, which further enhances the binding of the transcription factors XBP1 and EGR2 to LAG3 promoter. Reconstitution of ATM and inhibition of XBP1 or EGR2 in PCa T cells suppressed LAG3 expression and restored the effector function of CD4+ T cells from PCa. Our study revealed the mechanism of LAG3 upregulation in CD4+ T lymphocytes of PCa patients and may provide insights for the development of immunotherapeutic strategies for PCa treatment.


Assuntos
Neoplasias da Próstata , Linfócitos T , Masculino , Humanos , Linfócitos T/metabolismo , Transdução de Sinais , Regulação para Cima , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo
16.
Nanomicro Lett ; 15(1): 223, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37812339

RESUMO

Room temperature low threshold lasing of green GaN-based vertical cavity surface emitting laser (VCSEL) was demonstrated under continuous wave (CW) operation. By using self-formed InGaN quantum dots (QDs) as the active region, the VCSEL emitting at 524.0 nm has a threshold current density of 51.97 A cm-2, the lowest ever reported. The QD epitaxial wafer featured with a high IQE of 69.94% and the δ-function-like density of states plays an important role in achieving low threshold current. Besides, a short cavity of the device (~ 4.0 λ) is vital to enhance the spontaneous emission coupling factor to 0.094, increase the gain coefficient factor, and decrease the optical loss. To improve heat dissipation, AlN layer was used as the current confinement layer and electroplated copper plate was used to replace metal bonding. The results provide important guidance to achieving high performance GaN-based VCSELs.

17.
Diabetes ; 72(11): 1597-1608, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37625146

RESUMO

Obesity increases the risk of myocardial fibrosis, a pathological change in most heart diseases, but the mechanism has not been fully elucidated. Here, we found that mice with high-fat diet-induced obesity had more severe myocardial fibrosis than control mice under normal and ischemia/reperfusion (I/R) conditions, which could be alleviated by neutralizing antibodies against interleukin (IL)-1ß and IL-18, downstream products of the nucleotide-binding oligomerization-like receptor protein 3 (NLRP3) inflammasome, and the NLRP3 inhibitor MCC950. Mechanistically, mitochondrial hyperacetylation in obese mouse hearts recruited apoptosis-associated speck-like protein containing a CARD (ASC) to mitochondria and thus facilitated NLRP3 inflammasome assembly. Acetylation of K255 on hydroxyl-CoA dehydrogenase α subunit (HADHa) was identified to trigger the mitochondrial localization of ASC. Blockade of HADHa-K255 acetylation downregulated mitochondrial ASC, suppressed the NLRP3 inflammasome, and attenuated post-I/R myocardial fibrosis in obese mouse hearts. In obese human patients, the extent of myocardial fibrosis according to T1 MRI was positively correlated with the plasma levels of IL-1ß and IL-18, supporting the connection of NLRP3 inflammation to obesity-induced myocardial fibrosis. In conclusion, our study demonstrates that the heart is susceptible to fibrosis under obesity through hyperacetylated HADHa-mediated activation of the NLRP3 inflammasome.

18.
Org Lett ; 25(33): 6184-6188, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37559181

RESUMO

1,3-Functionalized cyclobutane structural motifs are ubiquitous in natural products and pharmaceuticals. Photoinduced alkylation of bicyclo[1.1.0]butanes (BCBs) offers a step-economical strategy for accessing 1,3-functionalized cyclobutane motifs. Herein, we disclose a general and mild photocatalytic protocol of bromoallylation and alkylation of BCBs in a metal, additive-free manner by using the same photocatalyst, 2-isopropylthioxanthone, in different catalytic roles. Furthermore, the synthetic utility of these products was illustrated in the synthesis of various valuable and complex cyclobutane derivatives.

19.
Front Immunol ; 14: 1147528, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37033934

RESUMO

Background: Zinc is a key mineral element in regulating cell growth, development, and immune system. We constructed the zinc metabolism-related gene signature to predict prognosis and immunotherapy response for lung adenocarcinoma (LUAD). Methods: Zinc metabolism-associated gene sets were obtained from Molecular Signature Database. Then, the zinc metabolism-related gene signature (ZMRGS) was constructed and validated. After combining with clinical characteristics, the nomogram for practical application was constructed. The differences in biological pathways, immune molecules, and tumor microenvironment (TME) between the different groups were analyzed. Tumor Immune Dysfunction and Exclusion algorithm (TIDE) and two immunotherapy datasets were used to evaluate the immunotherapy response. Results: The signature was constructed according to six key zinc metabolism-related genes, which can well predict the prognosis of LUAD patients. The nomogram also showed excellent prediction performance. Functional analysis showed that the low-risk group was in the status of immune activation. More importantly, the lower risk score of LUAD patients showed a higher response rate to immunotherapy. Conclusion: The state of zinc metabolism is closely connected to prognosis, tumor microenvironment, and response to immunotherapy. The zinc metabolism-related signature can well evaluate the prognosis and immunotherapy response for LUAD patients.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Zinco , Imunoterapia , Prognóstico , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/terapia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Microambiente Tumoral/genética
20.
Front Immunol ; 14: 1171145, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37081889

RESUMO

Background: As the main executor of immunotherapy, T cells significantly affect the efficacy of immunotherapy. However, the contribution of the T cell proliferation regulator to the prognosis of lung adenocarcinoma (LUAD) and immunotherapy is still unclear. Methods: Based on T cell proliferation regulators, LUAD samples from The Cancer Genome Atlas (TCGA) were divided into two different clusters by consensus clustering. Subsequently, the T cell proliferation regulator (TPR) signature was constructed according to the prognostic T cell proliferation regulators. Combined with clinical information, a nomogram for clinical practice was constructed. The predictive ability of the signature was verified by the additional Gene Expression Omnibus (GEO) dataset. We also analyzed the differences of tumor microenvironment (TME) in different subgroups and predicted the response to immunotherapy according to the TIDE algorithm. Finally, we further explored the role of ADA (Adenosine deaminase) in the lung adenocarcinoma cell lines through the knockdown of ADA. Results: According to the consensus clustering, there were differences in survival and tumor microenvironment between two different molecular subtypes. T cell proliferation regulator-related signature could accurately predict the prognosis of LUAD. The low-risk group had a higher level of immune infiltration and more abundant immune-related pathways, and its response to immunotherapy was significantly better than the high-risk group (Chi-square test, p<0.0001). The knockdown of ADA inhibited proliferation, migration, and invasion in lung adenocarcinoma cell lines. Conclusion: T cell proliferation regulators were closely related to the prognosis and tumor microenvironment of LUAD patients. And the signature could well predict the prognosis of LUAD patients and their response to immunotherapy. ADA may become a new target for the treatment of LUAD.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Prognóstico , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/terapia , Imunoterapia , Proliferação de Células , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Microambiente Tumoral
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